Disable Smilies in This Post. Show Signature: include your profile signature. Only registered users may have signatures.

*If HTML and/or UBB Code are enabled, this means you can use HTML and/or UBB Code in your message.

If you have previously registered, but forgotten your password, click here.

T O P I C R E V I E W

Rusty B

Here are links to PDF reports on alternate Mercury and Gemini configurations and missions. Some very interesting diagrams and reading. The files are from the NASA NTRS server.

Mercury spacecraft that could be guided to a precise landing, change orbits, that had a Gemini type adapter added with fuel cells etc, that were to be launched on an Atlas-Vega launch vehicle, and that had a camera installed for manned reconnaissance. An unmanned Mercury reentry test at lunar return velocities.

Gemini spacecraft that were to be space station ferry vehicles, Gemini spacecraft that were to conduct a photo survey of the moon and Gemini spacecraft that were to make a direct flight to the moon and land as a backup to Apollo.

Rusty, I'm glad you find this stuff online. I came across some of this material in the 70's at McDonnell, but was afraid to say anything because it was all marked "Confidential." That's where the goal of a "Fourteen Day Mission" came from.

Thanks for the Atlas/Centaur info. I also saw drawings for an Atlas/Agena/Mercury. September 1st 1959 was a very busy day.

dtemple

quote:Originally posted by Lou Chinal:That's where the goal of a "Fourteen Day Mission" came from.

I have long wondered why Gemini 7 was scheduled for 14 days. The official justification was to know for certain if a crew would be able to survive that long in weightlessness for a lunar mission.

Clearly a lunar mission did not require a 14-day flight. Apollo 11 lasted about eight days, so eight days, maybe even ten, seems long enough. I have long suspected 14 days had more to do with MOL than Apollo.

With the newly posted links about Gemini spacecraft applications, the 14-day flight seems to have been to test the longevity of the Gemini spacecraft for multiple purposes as well as for future missions beyond the first lunar landing. The 14-day flight could not have been flown for the singular purpose of furthering the goal of "landing a man on the moon and returning him safely to the earth" within the decade of the 60s.

Jim Behling

No, it had nothing to do with MOL and everything to do with Apollo. MOL was barely two years old. Apollo lunar flight profiles were not defined in 1965 and so they did not know the actual duration

Jay Chladek

There were likely many reasons for a 14 day mission. In those days, NASA was considering longer missions to the moon as well and scientists and medical doctors also like nice round figures. So "two weeks" looks good on their research. I also gather that the 14 day record was put there to set a space endurance record that the Soviets might have a difficult time matching at the time (and the Soviets didn't exceed that record until 1970 with Soyuz 9, which was a ramp up to their first Salyut mission).

Engineers also like to certify their equipment for longer periods than the bare mission minimum to give them some cushion. That was likely the case with the fuel cell stacks, which were a bit balky on Gordo and Pete's "Eight Days or Bust" Gemini 5 mission. But yes, some MOL hardware considerations were likely also at work behind the scenes since the USAF had plans to use fuel cell stacks to power to MOL for missions under 30 days (and use solar panels for missions lasting over 30 days).

After going thur all of these documents, I have a question. Could an Agena provide enough thrust to propel a Gemini on a free return trajectory around the moon? We already know that the heat shild could be beefed up to survive a reentry and the ECS would certanly last long enough to surport a 140 hour(I'm going by Apollo 13) mission.

Headshot

I do not believe the Agena had enough horses to send a Gemini around the moon. A 1965 study for such a mission included a Centaur transtage lofted by a Titan III. Gemini would be launched separately, dock with the transtage and fire its engine to put it on a free-return trajectory around Luna. The study is included with the Gemini XII NASA Mission Report by Apogee Books.

Headshot

As a follow-up to another part of this thread, I recall that MOL missions were to last 30 days. I was always under the impression that the 14-day mission goal was driven soley by Apollo requirements.

Jim Behling

quote:Originally posted by Jay Chladek:But yes, some MOL hardware considerations were likely also at work behind the scenes since the USAF had plans to use fuel cell stacks to power to MOL for missions under 30 days (and use solar panels for missions lasting over 30 days).

No, no MOL considerations. Not the same contractors and no input by the USAF for such a requirement or consideration.

Whizzospace

I've been fascinated by the Lunar Gemini concepts since the 1968 film "Countdown," which sends actor James Cann on his solo lunar landing flight under Project Pilgrim.

The producers placed a full standard Gemini onto a LM descent stage, which isn't wildly different from a couple of these proposals.